This invention relates to an improved apparatus for exposing photosensitive media.
Known print-making devices include a flat glass plate with a light source on one side and a door or curtain on the other side. Means are provided for drawing a vacuum between the door or curtain and the glass plate. This vacuum is drawn after an original film to be copied ("a negative or positive") and an overlying sheet of material containing a photosensitive layer (e.g. diazo) are positioned on the glass plate. The vacuum flattens the sheets against the plate. A light source is turned on for a predetermined period of time, such as determined by a timer, in order to expose the photosensitive layer. The exposed photosensitive sheet is thereafter developed.
In such prior devices, this procedure has required a substantial amount of manual manipulation to properly place the sheets in position for copying. Also, an amount of guess-work as to the proper exposure setting is required, resulting in less than satisfactory reproductions of the originals. In addition, vacuum seals in such devices are not satisfactory. Furthermore, such devices are frequently time-consuming and otherwise difficult to operate.
Therefore, an improved apparatus for exposing photosensitive media is required to overcome these and other problems.